It is known to use electronic devices to monitor attempted tampering of weapons. For example, U.S. Pat. No. 5,437,117 to Mackey, III describes a firearm safety device shaped like a bullet which can be inserted in the chamber of a firearm. The safety device produces an audible alarm when the firearm is moved or handled, thereby, for example, alerting of an attempt to steal the weapon. U.S. Pat. No. 5,715,623, also to Mackey, III describes a transmitter unit adapted for connection to a firearm which produces a non-audible alarm signal when the firearm is moved or handled. A discrete receiver unit, positioned at a remote location receives the signal from the transmitter and produces an audible alarm.
A disadvantage of the prior art is that if an unscrupulous person were to remove the alarm device from the weapon or, in some cases, tamper with the alarm device on the weapon, no detection is made of such mischievous activities. In other words, the device can remain intact and functioning and yet not trigger an alarm that the device has been removed from the weapon or otherwise tampered with.